<template>
  <div id="app">
    <ul>
      <li v-for="(item, index) in myArr" :key="index">{{ item }}</li>
    </ul>
    <button @click="run">走一走</button>
  </div>
</template>

<script>
export default {
  data() {
    return {
      myArr: ["帅哥", "美女", "程序猿"],
      newArr: ''
    };
  },
  methods: {
    run() {
      this.newArr = this.myArr[0]
      this.myArr.shift()
      this.myArr.push(this.newArr)
    }
  }
}
</script>